Reply by crank49

As far as I know, and I have not done extensive research, the only type collector in wide use by wood workers that does not run the debris through the fan are the cyclones. As Neil said, many bag type collectors have been upgraded by installing a homemade cyclone in the air stream before the fan to address exactly this problem. To keep the big stuff out of the fan would not even require an effecient cyclone; just a drop-out-box would work. Many of the comercially available “cyclone” trash can lids are not much more than that.